Cain
by koalakoala
Summary: Or, postcards from far away. / She kisses him ardently and his fingers are soft on her cheekbones and he can almost forget the impulse saying leave, now. Simon/Isabelle. Oneshot.


You know, if today was your birthday, shouldn't you be _getting _things, not giving them? Ah, whatever. You get this tragic, angst-fest of a fic. This is my first attempt at writing for this series and pairing, so tell me what you think. (This will probably be AU after COFA, btw.)

Reviews are presents, literally, and appreciated, so thanks.

I don't own TMI.

* * *

**Cain**, or postcards from far away

And now thou art **C**ursed from the e**A**rth. A fug**I**tive and a wa**N**derer shalt thou be.

* * *

The first postcard she gets is from Liberty Island. A clichéd and yet still probably tourist-luring shot of the lady (dull green) against a robin's egg blue sky. He must have known she'd hate it.

_Wish you were here. Not really. Kind of. Well, a lot._ –S.L.

Isabelle rolls her eyes but tapes it to her wallpaper, picture forward.

The second, third, and fourth postcards are from Washington D.C. The Lincoln Memorial, Washington Monument, and the White House. They're all white, she notices idly. Subconsciously racist, maybe. She wouldn't know or care because they're just some old statuesque buildings that she's never seen.

She isn't like him. Her home is Idris.

_Miss you_, he writes.

What she thinks looks like a lump of shiny metal, useless compared to the glass towers in Alicante, greets her next, and the Sears Tower. Chicago.

She pictures him in his touristy I HEART NEW YORK T-shirt, squinting up at the skyscrapers she's never seen. Comparing them to home.

I don't want to see where you're going, Isabelle thinks. I want to see you.

Apparently, he hears her. From some insignificantly infinitesimal town in Iowa he glues a picture of himself over a generic photo of endless waves of grain. She stares at it for a long time, she'll admit. At his fake lopsided glasses and an identical grin. Strategically-placed bangs.

_I miss New York. And you especially, but you already know that._

She thinks of Clary, who comes by every single day to glide her fingers over the glossy picturesque postcards and every week to hand her a new one. She lets her do it because she loves him too, but all the while Isabelle wants to scream, loud, _you're the one who did this to him, carving his shitty fate onto his forehead to save him and yourself. _

As if the Mark was anything close to salvation.

She doesn't care where he's wandering. He doesn't seem to, either, because eventually the postcards from random exotic countries end up blank where you're supposed to write we'rehavingsomuchfun and iloveyou.

Jace doesn't mock them. Not once. And somehow that hurts worse than if he did.

Half-dry memories in all the colors of her nail polish. Empty postcards. Silence speaks so much louder than words.

* * *

It's a year before he returns to her.

Clary bursts into her bedroom too early, and she's shoving a postcard into Isabelle's fingers. Central Park. She almost runs there in her pajamas. She would have, if Clary hadn't stopped her. Later she'd say that was a good thing, but at the moment it was utterly frustrating.

He's waiting, sitting on the familiar fountain. He looks older, somehow, or just more tired.

Isabelle finds she's crying as he crushes his lips to hers, burying his fingers in her tangled hair. God, it's been almost three hundred and sixty-five days since he's kissed her, and she doesn't think she can ever make up for it.

"Don't you ever leave me again," she says, not quite as desperately as that night, but close, clutching the leather jacket she'd made him wear.

_That_ night. She used him and he let her and it didn't blossom, it _mutated_, and, frankly, it terrified her. Because she's supposed to be fearless. And what kind of idiot is scared of loving someone?

Their names sounded good together and her parents disapproved for a while she forced herself to think that was all that mattered. (But it wasn't.) She tasted the words _his girlfriend_ on her tongue and decided she liked it. A lot.

"Don't," she says again, as if saying it a million times would make it possible or probable or something at least _close_.

He smiles bitterly and doesn't promise her anything.

* * *

Back in her room at the Institute, he touches all of his postcards glued and stapled and taped to her wallpaper.

"You kept them all," he says, not quite surprised. There's fifty-nine. Fifty-nine bright unfamiliar places, fifty-nine pictures she hates and loves. She gently brushes his bangs aside, and kisses his forehead. Precisely on his Mark of Cain.

He leans in (because he's _just_ taller than her, thank the Angel) and presses his lips to hers. She tastes sweetly sour, tugging off her boots and his jacket.

"Isabelle," he says. It feels like deja vu as she yanks him onto her bed. "Izzy, I can't stay. I have to go."

She sits up and sighs, tucking her legs closer. "Now?"

Simon sighs, too. "I love you so much, do you know that?"

She announces the words back as customary, and it's like tearing who she is in half. Because Isabelle Lightwood has never seriously said that to anyone. She isn't supposed to form attachments like this. Yet she kisses him ardently and his fingers are soft on her cheekbones and he can almost forget the impulse saying _leave, now._

"Let me come with you," she gasps.

He'd never ask her to, but she's insisting with swollen lips and those huge blue eyes and he can't even think about saying no, you can't.

(She's seventeen and three hundred & fifty days old when she runs away.)

* * *

The first few months, it's kind of actually fun. Her smiles are big and sanguine and his are endearingly unbelieving.

He genuinely thinks she looks more gorgeous than ever wearing jeans and a T-shirt, long india-ink-hair looped into a sloppy ponytail.

It's basically a road trip, full of cheap motels and junk food at gas stations and occasional demons she can handle easily. Frequent stops at local butcher shops to steal the blood of someone's dinner. He drinks it like it's coffee.

She, however, drinks real coffee.

They go to Vegas and end up making out in a ridiculously expensive hotel room because he obviously can't pass for twenty-one. He wouldn't be able to drink even if he could. He tells her he's a virgin and she laughs because she knew and says wryly, _why don't we fix that?_

She won't deny that she likes that power over him.

It's almost like she's invisible, like _Isabelle Lightwood_ is only a name of a girl on a MISSING poster and a mark for being fearless isn't cut always into her palm.

Simon laughs and watches her as she does it, telling her she's fearless enough without it. She disagrees.

All they're doing is pretending. It's just a reckless road trip, and they're just simon&izzy. Running away from the fact that they have no idea where they'll be a week or day or hour from every single moment.

And she feels _human_, like a mundane, and it's utterly refreshing. But she isn't human, not really. And you can't wear a mask forever. Either eventually or soon you peel it off and reveal another disguise, because life is just a shitty masquerade of liars and people avoiding the fact.

At least, her life is like that. She isn't so sure about his.

* * *

And it starts to tear her down. She grows to hate the smell of his car, the sourcream&onion chips only she can eat, the endless gas stations. She sleeps most of the day and stays up all night, because she's gotten used to his vampire idiosyncrasies he can't get rid of.

He's still sixteen and she's almost but not quite nineteen and she _loves_ him.

She says goodbye anyway.

No one could tell her she isn't slightly sadistic; it's practically how she was raised to be. A gold whip placed naive five-year old fingers. She'd _wanted_ to have it. And now she hates feeling out of control, like the Mark on his forehead is directing her (and especially him), and there's absolutely no sense of liberty she can cling to. There's no classic _it's not you, it's me_ on her part, because it _is_ him and he knows it.

He doesn't deserve this or her or anything so complicated. If anything, she does, because she might as well have killed her brother, lopsided glasses (like _his_ used to be) and dark hair and comic books clutched in too fucking _pure_ fingers.

"Say it, Simon. Say it and I'll stay."

"I _can't_."

"Three letters," she insists. He tries, _again_, but it burns his throat and can't reach his tongue. He chokes. Like always. He's damned in two godawful ways.

"Izzy, you know I can't," he says defeatedly, and she feels a twisted sense of gratification because she did know.

"And _I_ can't live like this anymore!" she cries, tossing back her hair. "I can't." She'd honestly rather be lonely and bitter and broken than keep pretending she can stand this insanity of a life.

He just looks at her, because he's always known this was inevitable, the way things are supposed to be. He's the wanderer, the fugitive. Cursed from the goddamn earth. And the Bible never ever says anything about another.

Dying was a blessing for Cain, probably. He won't even have that.

She kisses his cheek and his lips and goes back to New York, New York like she never left. No one says anything otherwise, and she desperately wishes they would. She's nocturnal and caustic to everyone and Alec looks at her wearily as if to say, _why did you even come back? _

It hurts.

Clary visits her with empty fingers and a frown that disappears whenever she's around Jace.

Simon doesn't call her and she hardly expected him to since he never did before. _If I hear your voice, it'll just be harder for me not to come back_, he'd said, before everything. When they were simple. She can't decide if simple was better than problematical.

She's left with soured memories. Insomnia. Fifty-nine postcards.

The more she stares at them (and she does it too often), the more fake they look. She spends one night carefully peeling them off and re-stapling them on the blank sides. Twelve have writing. The other forty-seven are as empty as she feels.

"God," she says.

As if this was just a game of Simon Says (how frustratingly _ironic_) and all he had to do was repeat it back to her.


End file.
